1. Field of the Invention:
This invention relates to a sewing equipment apparatus ideal for sewing sheet material having an extremely vast area, and more particularly to sewing apparatus capable of performing a so-called relay sewing process for sewing together the side end parts of adjacent broad cloths overlapped together, simultaneously for a plurality of cloths laid in the lateral direction.
2. Prior Art:
A sewing machine capable of performing the so-called relay sewing process of sewing with each edge part of two broad cloths overlapped with each other without folding the cloths is disclosed in Japanese Patent No. 1,232,866. The sewing machine disclosed in this publication is constructed as shown in FIG. 9, that is, a base end part 502a of an arm 502 to be set up on a bed 501 is disposed at the nearer side (arrow F side) of a needle location P', and this base end part 502a of the arm 502 is formed so that the shape of the section orthogonally intersecting with the cloth feeding direction may be approximately in a Z-form. In the sewing machine thus constructed, when feeding the cloths to the needle location side, each cloth to be sewn can individually pass through the upper side and lower side of the orthogonal part with the cloth feeding direction in the base end part in the approximately Z-form, so that all cloths may be smoothly sewn without having to be folded back.
Conventionally, however, in such a relay sewing process, an operator is used to join the side ends of two fabrics and assists by forwarding the cloths into the needle location by hand along with the feeding operation of the sewing machine.
Recently, to be, the cloth products to be formed by such a relay sewing process tend to be larger in size as compared with the former ones, as represented, for example, by a large-sized bellows type tent. These large cloth products can no longer be manufactured efficiently by such a method of sewing every two cloths. It is expected that such a problem will be solved when three or more cloths are sewn in the relay sewing process, but in the conventional general sewing machines, that is, in the machines having the base end part of the arm coupled to the bed at the side of the needle location this base end part, however, is an obstacle, so that the job of plaiting down the cloth located at the base end side of the arm from the needle location is needed, and because of this it was actually not considered possible to perform a relay sewing process simultaneously on three or more cloths.